One of the most striking elements in Rory Kennedy's affectionate and revealing documentary about her mother, Ethel Kennedy, is that those old enough to remember the assassination of Robert F. Kennedy in 1968 perhaps remember as well the shattering sense of grief and hopelessness that the shooting brought.

And yet, Ethel Kennedy, now 84, seems to have never lost hope and certainly not her deeply held religious faith. She believes that her husband and his brother, John, are in a glorious place with all her other family members who have died. She knows she will see them all again, believes it with all of her considerable heart.

The subject of "Ethel," airing Thursday on HBO, has not given an interview in more than 25 years. While some may think that sitting down to talk about her life with the youngest of her 11 children behind the camera is unlikely to yield a detailed or objective portrait, you will come away from the film understanding a great deal about an extraordinary woman who played much more than just a supporting role in a significant period in our history. Perhaps more important, you will get a better sense of that historic period as well.

From the election of John F. Kennedy onward, the nation got to know the two most visible of the Kennedy women: the reserved, patrician Jacqueline, who spoke in Marilyn Monroe-like near whispers, and the fun-loving, girl-next-door Ethel Skakel Kennedy, the wife of the president's closest confidant, his brother Bobby.

Shared grief

As different as they were, the two women had things in common: Although they understood that their grief over the assassinations of their husbands was shared by the nation, they each found ways to shield their families and themselves from too much scrutiny. Jackie, not always comfortable in the role of a political wife and shaken by Robert Kennedy's death, married a Greek tycoon and moved with her two kids to Skorpios. Ethel doubled down to raise her family, including her last child, Rory, born six months after Bobby's death.

To the public, Ethel Kennedy has always seemed to be the keeper of the flame of her husband's legacy of crusading for social justice. We understand from the film, however, that if anything, Ethel's commitment to social causes was even deeper than her husband's. That's why the younger children, in particular, who barely remember their father, say that Ethel's passion has been the primary source of inspiration for them.

Ethel Skakel had little interest in politics growing up, but once she got married in 1950 and found herself part of the very political Kennedy clan, she took to campaigning as if she'd been born into the family business. Her own family was Republican, by the way, and thought she was "a little communist."

Largely because of Jackie, and to a lesser extent, Ted Kennedy's first wife, Joan, there's always been a certain mythology about the role of women in the Kennedy clan and, in particular, about how a Kennedy wife was supposed to behave. If there was a family code of conduct, Ethel didn't feel bound to it. She seemed to do and say what she wanted to, sometimes without apparent consideration of political consequences. She was even arrested as a horse thief at one point after coming across a group of severely malnourished horses and promptly commandeering them to restore their health.

Although Rory Kennedy is the director, she doesn't always have a willing "star" in front of the camera. Asked about that June night at the Ambassador Hotel in Los Angeles in 1968, Ethel says simply, "talk about something else."

Children's deaths

Rory's narration mentions the deaths of her brothers, David, from a drug overdose, and Michael, from a skiing accident, but these aren't subjects Ethel wants to talk about.

She does talk about time after the assassination of John Kennedy, though, as "six months of just blackness."

Next year will mark the 50th anniversary of the Kennedy assassination, an event that has been extensively researched, documented and written about as few events in American history ever have. The Baby Boomer generation certainly remembers the impact of John Kennedy's death, the funeral that played out in black and white on their TV sets that weekend, the riderless horse accompanying the slain president's flag-draped coffin to Capitol Hill, and the on-air shooting of Lee Harvey Oswald by Jack Ruby.

The whole idea that a president could be assassinated in modern times was unthinkable, and there was, indeed, a period of blackness in the country, a pervasive, societal uncertainty that transcended grief.

But the decade was still new and the world was continuing to change. Our involvement in Vietnam wasn't about to go away just because we had a new president, and the swelling tide of the civil rights movement was not about to recede either.

Hope now flickered on a hillside beneath a postcolonial mansion in Virginia.

Five years later, the deaths of Martin Luther King Jr. and Robert Kennedy were every bit as shocking to the nation as the 1963 assassination. Back then, we had said, "It can't happen here," but it did.

Twice that spring in 1968, we said, "It can't happen again."

But to younger generations, these events may be merely history - significant, of course, but not occurrences they remember.

That's one of the reasons "Ethel" is an important film: We are hearing the voice of someone who was there and is still with us. Even viewers who were yet to be born when Robert Kennedy squared off against Jimmy Hoffa, when he brought the power of the federal government to bear against segregation in the South and when he defied the label of "carpetbagger" when he ran successfully for the Senate from New York will understand the dynamic of hope that the Kennedy mystique still carried, even after Dallas.

American politics would become a much more cynical business after Robert Kennedy's death, especially by the early '70s, with the stain left by the Watergate break-in and the Nixon resignation. Many lost degrees of hope as the years went on, but one woman never has - not because she's covered her eyes to reality but because she's a survivor.

"Nobody gets a free ride," she says. "So have your wits about you, and do what you can and dig in, because it might not last."